The present invention relates to safety helmets and more particularly to safety helmets with visors used by pilots and crew in high performance aircraft.
Prior art safety helmets used by pilots and crew of high performance aircraft such as the F-4 or F-14 fighters have caused considerable discomfort during high head-to-seat acceleration such as in a pull-out from a dive because the greater concentration of weight in the helmet front tends to rotate the helmet forwardly against the face of the aircrewman. If ejection from the aircraft becomes necessary, the windblast against such helmets also resulted in severe discomfort or even injury. The dynamic air pressure inside the helmet shell as well as beneath the visor guard creates a lift force which is imparted to the pilot's head. Windblast frequently causes the helmet visor to fracture and be blown off of the helmet or forced into the pilot's face. Furthermore, prior art helmets are very uncomfortable due to lack of ventilation and cooling. One solution to that problem was the bulky and power consuming forced air cooling system. In other helmet designs, cloth hat suspensions provided cooling, but ventilation was limited to the periphery of the helmet shell.